New SVG icon don't change its color when switching to dark mode.

[abwildan]

Describe the bug
I add new svg icon for website's menu icon, but its color didn't change during light and dark mode switch. It should be white in the dark mode, but it stays black.

To Reproduce
Steps to reproduce the behavior:

1. I downloaded a couple of svg icons from this site: https://www.svgrepo.com/svg/ and put it in /assets/icons directory.
2. Then I add the icon name in /config/_default/menus.en.toml, especially in Tech & Chess pre variable, respectively.
3. It showed perfect in size and default color (black), but, when I switched the mode to dark, the color of the icon didn't change.

Expected behavior
Another default icon from your themes behave as it is, it is black in light mode and white in dark mode. However, the new icons didn't do like the defaults.

Screenshots

vid1.mp4

Desktop (please complete the following information):

• OS: Archlinux
• Kernel: 6.12.8-arch1-1
• Browser: Firefox
• Version: 133.0.3 (64 bit)

Hugo & Blowfish versions
Hugo version: hugo v0.140.2+extended linux/amd64
Blowfish version: 2.81.0